Typically, telecommunication systems that provide broadband access to residential customers contain a residential gateway which consists of an xDSL (any type of digital subscriber line generally communicated over copper lines) modem or xPON (any type of passive optical network generally communicated over optic fibers) interface combined with various local area networking (LAN) technologies to enable sharing the broadband access with other computers or devices within the residence. Wireless local area network standards and home phone line networking (HPNA) are examples of such LAN technologies. In addition, some telecommunication systems may provide a voice-over-internet-protocol (VOIP) feature to allow telephone calls via the broadband link. Some systems may, in addition to broadband access sharing, need to distribute broadband media content such as video streams into various locations within the residence.
Typically the residential gateway is located inside the house. However, it is desirable to locate the residential gateway at the network interface device (NID) outside the house. A NID is the point of demarcation between the Unbundled Network Element (UNE) loop and the end user's inside wire. Reasons for desirability of locating the residential gateway at the NID include to provide simplified installation wiring and to eliminate the need to have the user home when the bulk of installation occurs. Further, as fiber to the neighborhood rolls out, integration will be easier if the active electronics are already present at the NID. Also, installation practices can be merged between xPON and xDSL systems such that the primary network termination is the mere difference.
However, a significant problem in trying to locate the residential gateway at the NID is the problem of providing power. There is often no external source of alternating current (AC) power accessible at the NID location.
Another problem includes communicating between devices that are not able to share a common electrical ground. Current schemes for these communications are relatively expensive for conducting multiple channels of synchronous high speed data. These current schemes for providing multiple channels of synchronous high speed data between devices which can not share a common electrical ground require the use of expensive optoelectronics or the use of high frequency modulation schemes. These schemes consume large amounts of power and add substantially to the complexity of the communication links